Tab anti-rotation and hold down device

ABSTRACT

An improved pull tab mounting arrangement for an easy open end closure member, characterized by the provision of improved pull tab positioning means for maintaining the pull tab in a desired orientation relative to the panel-defining score line and minimizing tab protrusion from the end closure member. A pierced hole forming a protrusion with a jagged edge is incorporated in the tab nose portion between the free extremity of the tab and the rivet means that secures the tab to the end panel member. The jagged protruding edge of the protrusion is driven into the end panel member during the staking operation, thereby providing an anti-rotation interlock between the tab and the end panel which prevents rotation of the tab nose relative to the score line. The protrusion further serves to raise the nose portion of the tab relative to the end panel thereby biasing the tab against the end panel upon staking of the rivet which forces the finger grip portion of the tab into close contact with the end panel.

SUMMARY OF THE INVENTION

The present invention relates to a new and useful improvement in an easy opening container and more particularly to a pull tab mounting arrangement for improving the opening characteristics thereof.

Easy opening containers of the general type to which the present invention relates include an end closure formed with a score line to define a removable panel portion for tilting movement so that a nose on one end of the tab initially severs the score line. Thereafter, a pulling force is applied on the pull tab to completely separate the removable panel portion along the score line from the end unit and thereby provide an opening in the end closure.

It is an object of the present invention to improve the opening characteristics of the pull tab to initiate the severance of the removable panel portion from the end unit.

This is accomplished by providing a mounting arrangement in which the pull tab nose is maintained in proper alignment with the score line. More specifically, the pull tab is mounted in a manner such that it is restrained against rotation to maintain the nose of the pull tab aligned with the score line so that upon initial tilting, the score line is severed by the tab nose.

It is another object to reduce the protrusion of the pull tab from the end member, thereby improving the appearance of the container and eliminating the possibility of accidental opening of the container during handling.

This is accomplished by providing a mounting arrangement which downwardly biases the finger grip portion of the tab. More specifically, the nose portion of the tab is maintained in spaced relation to the end panel thereby bowing or springing the tab toward the end panel during the staking operation and imparting a downward bias on the finger grip portion of the tab.

It is a primary object of the invention to provide an inexpensive, easily manufactured anti-rotation device on the tab which co-operates with a flat plate section of the end panel and which is forced to dig into the end panel by the staking of the rivet which attaches the tab to the panel.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more readily understood by reference to the following description, the appended claims and the several views illustrated in the accompanying drawings.

IN THE DRAWINGS

FIG. 1 is a top plane view of a can end closure incorporating the improved pull tab mounting arrangement of the present invention.

FIG. 2 is an enlarged fragmentary perspective view of the tab illustrating jagged protruding edges of a projection formed by piercing a hole through a portion of the tab.

FIG. 3 is an enlarged fragmentary sectional view of the end closure, illustrating the manner in which the jagged protrusions on the tab dig into the end panel.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In keeping with the present invention, there is provided an easy-open end closure comprising a metal end panel 1, a rivet 2 integrally formed in said end panel 1 and a metal pull tab 3 rotatably attached to said end panel 1 by said rivet 2. A score line 4 is formed in the end panel 1 and defines an opening flap 5 therein.

The tab 3 comprises a nose portion 6, an intermediate portion 7 and a finger grip portion 8. A hole 9 is pierced through a portion of the tab 3 and forms a jagged protrusion 9a with points 10 adjacent to the nose portion 6 between and in line with the free extremity of the tab 3 and the rivet means securing the tab 3 to the end panel 1. A peripheral rigidifying bead 11 encircles the tab 3 and facilitates removal of the flap 5.

During the staking operation, wherein the tab 3 is fastened to the end panel 1, the tab 3 is forced downwardly onto the end panel 1, the jagged protrusion 9a being driven into the end panel 1, whereby the points 10 engage the metal of the end panel 1, thereby preventing rotation of the tab 3 about the rivet 2 and maintaining the pull tab nose in alignment with the score line 4.

The protrusion 9a further serves to raise the nose portion 6 relative to the end panel 1 and to maintain said portion 6 in spaced relation to said end panel 1. This spacing causes the tab 3 to become slightly bowed or sprung toward the end panel 1 when the intermediate portion 7 is fastened in close contact to the end panel 1 by the rivet 2. The resilient, flexible tab 3 is thus subjected to a bending moment which panelwardly biases both the finger grip portion 8 and the nose portion 6 and insures close contact is maintained between both of said portions and the end panel 1. 

I claim:
 1. An improved pull tab mounting arrangement for an easy-open end closure member, said end closure member comprising an end panel, a pull tab having a finger-grip portion and a nose portion, means rotatably attaching said tab to said end panel, and a score line formed in said end panel in position to be opened by said nose position and defining an opening flap therein, the improvement comprising; tang means on the tab for interlocking engagement of said tab and said end panel against displacement of said nose portion to a non-operative position with respect to said score line, said tang means comprising a jagged, panelwardly directed protrusion formed in said tab and impaled into said end panel, said tang means urging said nose portion away from said end panel and biasing said finger-grip portion of said tab panelwardly and holding the same against said end panel.
 2. An improved pull tab mounting arrangement as described in claim 1 wherein said attaching means comprises rivet means integrally formed in said end panel, said rivet means being attached to the tab in an area loading said tab with a bending movement.
 3. An improved pull tab mounting arrangement as described in claim 2 wherein said protrusion is located in the nose portion of said tab between the free extremity of tab and said rivet means.
 4. An improved pull tab mounting arrangement as described in claim 1 wherein said jagged protrusion is the peripheral edge of a pierced hole formed in the tab.
 5. An improved pull tab mounting arrangement as described in claim 3 wherein said protrusion is located in line with a free extremity of the nose and said rivet means.
 6. An improved pull tab for an easy-open end closure member, said end closure member comprising an end panel, a pull tab having a finger-grip portion and a nose portion, means rotatably attaching said tab to said end panel, and a score line formed in said end panel and defining an opening flap therein, the improvement comprising a jagged ended, panelwardly directed projection formed in said tab, the jagged end of said projection being driven into said end panel and biting into said end panel thereby preventing displacement of said nose portion of said tab to a non-operative position with respect to said score line, said projection co-operating with said attaching means to bias said finger-grip portion of said tab panelwardly to prevent protrusion of the tab. 